Film cleaning device



Oct. l, 1946. B, E, MlLLS 2,408,438

A FILM CLEANING DEVICE i f Filed June 1 8, 1942 5 Sheets-Sheet 1 oct. 1, 1946.y B, E, MILLS Y 2,408,438

I FILM CLEANING DEVICE Filed June 18, 1942 5 Sheets-Sheet 2 oct. 1, 1946. B, E MILLS 2,408,438

FILM CLEANING DEVICE Filed June 18, 1942 5 Sheets-Sheet 4 001:. l, 1946. B. E, MlLLs v 2,408,438

FILM CLEANING DEVICE Filed June 18; 1942 5 sheetsfsh'eet 5 Patented Oct. 1, 1946 UNITED STATES PATENT OFFICE FILMl CLEANING DEVICE of Illinois Application June 18, 1942, Serial No. 447,605

1' 10 Claims. This invention relates to a device for cleaning motion picture lm and is adapted for use as an attachment to a motion picture projector so as to clean the film in the course of its travel from the lm coil to the projector lens. It is, however, also adaptable for use at other points or in connection with other film handling apparatus, as, for example, lm winding apparatus or means for transferring the film from one reel to another.

The principal object of the invention is to provide a device whereby, a film cleaning solution may be uniformly applied to the film through the medium of lm wiping elements and in which the control of said elements and the feeding of the cleaning solution thereto are controlled in such manner as to obtain the desired result with a minimum amount of complication and difficulty.

A further object of the invention is to provide in such a film cleaning device means for causing the device to become inoperative when the supply of cleaning solution becomes exhausted or reaches a predetermined low level inthe receptacle from which it is supplied.

A further object of the invention is the provision of means for controlling the movement of the elements of the film wiping device into and out of engagement with the film in coordination with the supply of 'cleanin'g'solution to said elements so that such solution is supplied only when they are in operative position.

Other objects and advantages of the invention will be apparent from the following description of a preferred embodiment thereof, taken in connection with the accompanying drawings, in which:

Fig. 1 is a side elevational view of a motion picture projector equipped with the nlm cleaning device of my invention;

Fig. 2 is an enlarged frontvview, partly broken away, showing portions of the film cleaning device;

Fig. 3 is a sectional and elevational. view of the supply tank for the cleaning solution and ther valve mechanism for controlling the flow of solution therefrom, being takenfsubstantially on the line 3-3 in Fig. 2;

Fig. 4 is a top plan View of the mechanism shown in Fig. 3;

Fig. 5 is a sectional view taken substantially on the section line 5-5 of Fig. 3;

Fig. 6 is a diagrammatic view of certain of the electromagnets and other electrical devices and wiring by which the operation of the device is controlled; and

Fig. '7 is a continuation of Fig. 6, showing the master relay and the starting switch, which may be coin-controlled.

In said drawings the lm coil, indicated by the reference numeral II is mounted in a film holder I2 supported on a frame I3 of a motion picture projector. The film from the coil is paid out from the center by means of a pay-out roller I4, which preferably is angularly mounted and directsV the film into a plane of travel laterally disposed with respect to the film coil Il, in which plane it passes through theV projector, being then returned to the exterior of the coil on which it is wound by rotation of the coil. The film is drawn from the inside of the coil by means of a feed sprocket I5 of the projector mechanism and passes around a guide roller I6, the payout roller I4, a guide roller l'l, and additional guide rollers I8, I9 and 2l to said sprocket I5. The film, which is identified by the numeral 22, then passes through the projector lens mechanism, generally indicated by the numeral 23, and over a sound head roller 24, a second sprocket 25 and rollers 26, 21 and 28 back to the coil Il. The pay-out roller I4 is, or may be, driven by means of a belt 29 from a source of power (not shown) for thesprockets I5 and 25. The projector mechanism is not described in further detail since it is believed that other details thereof are'not essential to an understanding of the present invention.

As the film passes between the rollers IB and I9 it is cleaned by the device of my invention which includes two pivoted wiper elements 3| and 32 which carry pads 33 of felt or like absorbent material adapted to be moved into engagement with opposite sides of the film when the. cleaning device is operated, as will be hereinafter described.

Cleaning solution is supplied to said pads from a tank 34 through pipes 35, the rate of flow being regulated so that said solution will drip onto said pads at a desired rate of flow controlled by means of hand-operated valves 36 extending into couplings 31 screwed into bosses 38 on the bottom of the tank 34, said couplings each having staggered passages 39 and 4I therein, with an opening 42 communicably connecting the same, and with the point of the valve member 36 extending into said opening to a variable extent depending uponV the position of adjustment of the valve. (See Fig. 3'.)

In the bottom ofthe tank 34 there is provided a plate 43 supported upon a spacer ring 44 to which said plate is tightly secured by means of screws 45. Said ring 44 and plate 43 provide the side and top walls, respectively, of a relatively small chamber 4G which communicates through openings 41 in the bottom of the tank 34 with the passages 39 in the couplings 31.

There is an opening 48 in the plate 43 into which extends the pointed end oi' a valve member 49 which is disposed vertically through the cover 5| ci the tank 34 and through a guide member 52 formed on the top of said plate 43.

The upper end of said valve member 49 is com nected by means of a pin '53 with a lever 54 pivoted at 55 to ears 56 on the cover 5|, said lever 54 being connected by a link 51 with an armature 58 of an electromagnet 59 carried upon a support 6| on a bracket 52, which is welded or otherwise secured to a bracket S3 on which the tank 34 is supported, the latter bracket being in turn supported upon a frame arm 64.

The armature 58 is pivoted at 65 to a lug 65 on the bracket 82 and is normally held in the raised position shown in Fig. 3 by means of a spring Gl' secured at the upper end to a projection 63 on said armature 58, and at the other end to a lug @il on the bracket G2.

In the tank 34 there is provided a iloat 1| carried at the end of an arm 12 which is pivoted at 13 to ears 14 on the top of a plate 43. A push rod 15 is secured to said arm 12 intermediate the ends of the latter and extends upwardly through the cover 5|, having at its upper end a head 16 engaging a lower spring member 11 of a switch 1S. of said switch are mounted in vertically spaced relation in a post 8| on said top member 5| of the tank 34, and are connected into an electrical circuit by means of wires 82 and 83 sho-wn in Figs. 1, 4 and 6 of the drawings.

A filler cap 84 is provided on the cover 5|, through which a cleaning solution, such, for eX- ample, as carbon tetrachloride, may be poured into said tank 34.

A second magnet 85 is supported at the lower end of the bracket 63 and beneath said magnet is a pivoted armature 86 carrying at its outer end a roller 81 disposed between lower extensions 8B and 89 on the arms 3| and 32. Said arms 3| and 32 are spring-biased or weighted so as to normally be in open position with the pads 33 separated, and said extensions BS and 89 diverge from the pivot 9| on which said arms are mounted so that when the roller 81 moves upwardly between said extensions the upper parts of the members 3| and 32 will be moved toward each other, bringing the pads 33 into contact with the i'ilm 22.

A third magnet, identified by the numeral S2 (see Fig. 6) is provided for controlling the energization of the valve magnet 59 and cleaner magnet 85, said magnet 92 being mounted in a conveniently located box (not shown) on the frame of the projector. The circuit, including wires Q3 and 94, to said magnet 92 is adapted to be momentarily closed by means of a manually operable switch 95. When energized, said magnet attracts an armature G5 which is connected to movable members 91 and 90 of switches 99 and lill, respectively, both of which are closed by movement of said armature toward the magnet. The switch 99, being in parallel with the switch S5 causes the magnet 92 to remain energized after momentary operation of the switch '95 until the circuit is broken by opening of the switch 18 when Said member 11 and an upper member T9 y,

the liquid level in the tank 34 falls to a predetermined point.

The connections between the above-described magnets and switches and with the source ol' power are made through suitably located terminal blocks |03 and |04. The connections to the source of power and to a master relay shown in Fig. '7 are indicated at |02.

In said Fig. 7 have shown a line connection im) and a master relay Hill. The latter comprises a magnet |05, an armature |05 which is normally biased to open position, and a switch lill comprising a xed member |98 and a movable member |09 which is connected to a projection lll carried at the end of the armature |06. Thus when the magnet is energized said switch |31 Y is closed and when it is deenergized the switch is opened.

For controlling said master relay |65 a switch |2 is provided, comprising a iiXed member l i3 and a movable member H4, the latter being biased to closed position and normally held in open position by a projection H5 on the end of a pivoted lever H which rests on a pin ll'l on a ratchet wheel ||8 of a coin control device ol known construction. Said wheel is spring-biased to rotate in clockwise direction and is permitted to move one step in such direction for each coin deposited, such movement being controlled by an escapement lever ||9 connected by a link |24 with an armature |25 of a step-up solenoid |26 in circuit with a coin switch |21. Upon the iirst step the pin Il moves downwardly a sufficient distance to permit the lever li and projection H5 thereon to move far enough away from the switch member ||4 to allow the switch H2 to close. A step-back solenoid |21, controlled by a cut-oi switch |28 and having an armature |22 carrying a pawl |23, arranged to engage the teeth of the ratchet wheel ||8 serves to turn said wheel back one step for each cycle of operation in manner which will be understood by those familiar with coin devices of this general character, and when the pin ||1 is restored to its original position the lever i6 and rod l i5 will be raised to the point that the switch i2 will be opened, thus terminating the operation oi' the machine.

The closing of the switch lill, in conjunction with the operation of the master relay Ifit, causes the magnets 59 and 85 to be energized, thereby opening the valve i521, 49 (Fig. 3) and moving the wiper armsI 3| and 32, and the pads carried thereby, into operative relation to the film 22. Drops of cleaning solution are 'then supplied to the pads 33 and the latter clean the iilm as the same passes there-between. This condition contirrues until the master relay opens or the magnet 92 is deenergized by the opening of the switch 18 which is controlled by the liquid level in the tank 34. Thereupon the magnets 59 and 55 are deenergized, with the result that the valve 42, 49 is closed by upward movement of the armature 58 when released by the magnet 5.3 and the wiping elements are moved to inoperative `position in consequence of downward movement ofthe roller 81 when the armature 86 is released by the magnet G5.

When the tank is refilled to the point that the switch 18 is closed and when the master relay is again energized, the wiping device can again be rendered operative by momentary operation of the switch 95 and the cycle `of operation will then be repeated.

The foregoing detailed description has been .amarres given 'for olearness of understanding only, and no'unnecessarylimitations should be understood therefrom, but the appended claims should be construed as broadly as permissible in view of the prior art.

I claim:

1. A film cleaning device comprising movably mounted wiper elements disposed, respectively, on oppo-site sides of the iilm, electrically-con trolled actuating mechanism for moving said Wiper elements into contact with the film in a course of travel of the latter, said Wiper elements being equipped with absorbent contact pads, a supply tank for cleaning solution, an outlet valve for said tank, electromagnetic means for controlling the operation of said valve, means under the control of an operator for causing energization of said electromagnetic means to open said valve, means coordinated with said wiper-actuating mechanism for supplying the cleaning solution from said tank to said absorbent pads with a regulated rate of flow only When said Wiper elements are in operative position, and means controlled by the volume of the solution in said tank for causing deenergization of said electromagnetic means and closing of said valve when the quantity of cleaning solution in the tank drops to a predetermined point.

2. A film cleaning device comprising Wiper elements movable into contact with the nlm in a course of travel of the latter and equipped with absorbent contact pads, a supply tank for cleaning solution, an outlet valve for said tank, electromagnetic means for controlling the operation of said valve, means under the control of an operator for causing energization of said electromagnetic means to open said valve, means for conducting the cleaning solution from said tank to said absorbent pads with a regulated rate of flow, and means arranged to be automatically operated after predetermined operation oi the device to cause deenergization of said electroH magnetic means and closing of said valve.

3. A film cleaning device comprising Wiper elements movable into contact with the film in a course of travel of the latter and equipped with absorbent contact pads, a supply tank for cleaning solution, `an outlet valve for said tank, electromagnetic means for controlling the operation of said valve, means under lthe control of an operator for causing energization of said electromagnetic means to open said valve, means for conducting the cleaning solution from saidv tank to said absorbent pads with a regulated rate of flow, and means arranged to be automatically operated after predetermined operation of the device to cause deenergization of said electromagnet means and closing of said valve and to cause said movable Wiper elements to move out of nlm-engaging position.

4. A iilm cleaning device comprising Wiper elements movable into contact with the lm in a course of travel of the latter, a supply tank for cleaning solution, an outlet valve for said tank, electromagnetic means for controlling the operation of said valve, means under the control of an operator for causing energization of said electromagnetic means to open said valve, means for conducting the cleaning solution from said tank to said wiper elements with a regulated rate of flow, and means arranged to be automatically operated after predetermined operation of the device to cause deenergization of said electromagnetic means and closing of said valve.

5. A iilm cleaning device comprising Wiper elements engageable with the iilm in a course oi' travel of the latter, means for'supplying a cleaning solution to said Wiper elements, electro-magnetic means for controlling the movement of said wiperelements into and out of operative position, electromagnetic means for controlling the supply of said cleaning solution to said wiper elements, and means for controlling both said electromagnetic means to cause the same to be energized and deenergized simultaneously, whereby cleaning solution is supplied to said Wiper elements only when the latter are in nlm-engaging position.

6. A film cleaning device comprising wiper elements engageable with the nlm in a course of travel of the latter, means for supplying a cleaning solution to said Wiper elements, electromagnetic means for controlling the movement of said wiper elements into and out oi operative position, electromagnetic means for controlling the supply of said cleaning solution to said Wiper elements, and means, including a control magnet, for causing simultaneous energization oi both said electromagnetic means at the beginning of a period of operation to move said wiper elements into contact with the lm and to cause feeding of said cleaning solution to said elements, deenerglzation of said control magnet causing simultaneous deenergization of both said electro magnetic means to cause movement of said wiper elements out of film-engaging position and to cut oil the flow ci cleaning solution thereto.

'7. A lm cleaning device comprising Wiper elements engageable with the iilm in a course of travel of the latter, means for supplying a cleaning solution to said wiper elements, electromagietic means for controlling the movement of said Wiper elements into and out of operative position, electromagnetic means for controlling the supply of said cleaning solution to said wiper elements, means, including a control magnet, for

ycausing simultaneous energization of both said electromagnetic means at the beginning of a period of operation to move said wiper elements into contact with the nlm and to cause feeding of said cleaning solution to said elements, deenergization of said control magnet causing simultaneous deenergization of both said eiectromagnetic means to cause movement of said Wiper elements out of nlm-engaging position and to cut off the iow of cleaning solution thereto, said means for supplying cleaning solution including a supply tank, and means controlled by the volurne of cleaning solution in said tank for causing deenergization of said control magnet When said Volume falls to a predetermined point.

VA film cleaning device comprising Wiper elements engageable with the iilm in a course of travel thereof, means for supplying cleaning solution to said Wiper elements, and electricallyoperated control devices for moving the wiper elements into and out of engagement with the iilm and for causing the feeding of cleaning solution to said wiper elements only when they are in film-engaging position.

9. In a motion picture projector, a film cleaning device comprising Wiper elements engageable with the lm in the course of travel thereof from the film coil to the projector lens, a supply tank from which cleaning solution may be supplied to said Wiper elements, an outlet valve in said tank, and electricallyoperated means for controlling operation of said nlm Wiper elements and said outlet valve, whereby the valve is opened able, electrically-controlled mechanism responsive to actuation of said starting element for moving said wipers into nlm-engaging position and, after a. predetermined film-cleaning operation, caus- 5 ing disengagement thereof from the film.

BERT E. MILLS. 

